4.1.1

Angles & Lines

Test yourself

Types of Angle

There are 4 important types of angle:

Illustrative background for Right angleIllustrative background for Right angle ?? "content

Right angle

  • A right angle is an angle of 90° and is indicated by a square angle marker.
Illustrative background for Acute angleIllustrative background for Acute angle ?? "content

Acute angle

  • An acute angle is one that is less than 90°.
Illustrative background for Obtuse angleIllustrative background for Obtuse angle ?? "content

Obtuse angle

  • An obtuse angle is one that is greater than 90° but smaller than 180°.
Illustrative background for Reflex angleIllustrative background for Reflex angle ?? "content

Reflex angle

  • A reflex angle is greater than 180° but smaller than 360°.

Geometry Basics

Illustrative background for Vertices and edgesIllustrative background for Vertices and edges ?? "content

Vertices and edges

  • The corners of a polygon are called vertices and the sides are called edges.
Illustrative background for PlaneIllustrative background for Plane ?? "content

Plane

  • A plane is a flat 2 dimensional surface like the surface of a table.
Illustrative background for Parallel linesIllustrative background for Parallel lines ?? "content

Parallel lines

  • If two lines are parallel they point in exactly the same direction and will never meet.
  • Parallel lines are indicated by drawing matching arrows on the lines.
  • If there are two different pairs of parallel lines then different arrows are used for each pair.
Illustrative background for Perpendicular linesIllustrative background for Perpendicular lines ?? "content

Perpendicular lines

  • Two lines are perpendicular if the angle between them is a right angle.

Jump to other topics

1Numbers

2Equations, Formulae & Identities

3Sequences, Functions & Graphs

4Geometry

5Vectors & Transformation Geometry

6Statistics & Probability

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium